Melatonin Serum Levels in Rheumatoid Arthritis

Objective: Recent studies suggest that endogenous melatonin (MLT) production might play a role in the etiology of rheumatoid arthritis (RA). However, the role of MLT in RA pathogenesis remains unclear. This study was performed to determine MLT serum levels in RA patients.Materials and Methods: Twenty nine patients with RA and in 25 age- and sex-matched healthy controls were included in our study. Blood samples of the participants collected at 8AM. MLT was measured by enzyme-linked immunosorbent assay (ELISA). The MLT levels of the patients with RA were compared with healthy age- and sex-matched controls. The Mann-Whitney U-test was used to compare the data between the two groups.Results: MLT concentrations were significantly higher in RA patients than in the controls (p<0.05).Conclusion: Our results suggest that the higher blood concentrations of MLT in RA patients, especially in the early morning, may help to explain the morning stiffness and joint swelling. Turk J Phys Med Rehab 2013;59:42-4.